Authentication system

Abstract

The present invention aims to provide an authentication system that can accurately identify a genuine product. In an authentication system, a host instructs an authentication chip master to start authentication. In conjunction with the authentication start execution instruction, the host instructs a timer counter to start timer counting. In response to the authentication start execution instruction from the host, the authentication chip master outputs a challenge code to an authentication chip slave. The authentication chip slave performs an encryption process with respect to the challenge code. Then, the authentication chip slave outputs a response code obtained as the result of the encryption process, to the authentication chip master. Then, the authentication chip master performs a response code matching process, and outputs the authentication result to the host. In response to the authentication result, the host stops timer counting, and performs a verification process to accurately identify the genuine chip.

1 . An authentication system comprising:
 a body chip; and   a sub chip coupled to the body chip to perform an authentication process with the body chip,   wherein the sub chip includes a first encryption processing unit for performing an encryption process multiple times in response to an authentication execution instruction from the body chip, and then outputting the result of the encryption process to the body chip,   wherein the body chip includes an authentication determination unit for determining whether the sub chip is valid or not, based on the result of the encryption process received from the sub chip, and on the time from the authentication execution instruction until the result is obtained.   
     
     
         2 . The authentication system according to  claim 1 ,
 wherein the body chip includes:   a second encryption processing unit capable of performing an encryption process multiple times; and   a timer for measuring the authentication time,   wherein the authentication determination unit outputs a challenge code to the first and second encryption processing units as the authentication execution instruction,   wherein the first and second encryption processing units perform the encryption process multiple times with respect to the challenge code, and output first and second response codes as the results of the encryption processes, respectively, to the authentication determination unit,   wherein the authentication determination unit determines whether the first and second response codes match or not,   wherein if the first and second response codes match, the authentication determination unit determines whether the authentication time measured by the timer is within a predetermine time,   wherein if the authentication time is within the predetermined time, the authentication determination unit determines that the sub chip is valid.   
     
     
         3 . The authentication system according to  claim 1 ,
 wherein the body chip includes:   a second encryption processing unit capable of performing an encryption process multiple times; and   a timer for measuring the authentication time,   wherein the authentication determination unit outputs a first challenge code to the first and second encryption processing units as the authentication execution instruction,   wherein the first and second encryption processing units perform one-time encryption process with respect to the first challenge code, and output first and second respond codes as the results of the encryption processes, respectively, to the authentication determination unit,   wherein the authentication determination unit determines whether the first and second response codes match or not,   wherein if the first and second response codes match, the authentication determination unit outputs a second challenge code to the first and second encryption processing units,   wherein the first and second encryption processing units perform the encryption process multiple times with respect to the second challenge code, and output third and fourth response codes as the results of the encryption processes, respectively, to the authentication determination unit,   wherein the authentication determination unit determines whether the third and fourth response codes match or not,   wherein if the third and fourth response codes match, the authentication determination unit determines whether the authentication time measured by the timer is within a predetermined time,   wherein if the authentication time is within the predetermined time, the authentication determination unit determines that the sub chip is valid.   
     
     
         4 . The authentication system according to  claim 1 ,
 wherein the body chip includes:   a second encryption processing unit capable of performing an encryption process multiple times; and   a timer for measuring the authentication time,   wherein the authentication determination unit outputs a first challenge code to the first and second encryption processing units as the authentication execution instruction,   wherein the first and second encryption processing units perform one-time encryption process with respect to the first challenge code, and output first and second response codes as the results of the encryption processes, respectively, to the authentication determination unit,   wherein the authentication determination unit determines whether the first and second response codes match or not,   wherein if the first and second response codes match, the authentication determination unit outputs a second challenge code as well as information on the number of times the encryption process is performed, to the first and second encryption processing units,   wherein the first and second encryption processing units repeat the encryption process for the number of times specified in the number of times information, with respect to the second challenge code, and output third and fourth response codes as the results of the encryption processes, respectively, to the authentication determination unit,   wherein the authentication determination unit determines whether the third and fourth response codes match or not,   wherein if the third and fourth response codes match, the authentication determination unit determines whether the authentication time measured by the timer is within a predetermined time,   wherein if the authentication time is within the predetermined time, the authentication determination unit determines that the sub chip is valid.   
     
     
         5 . The authentication system according to  claim 1 ,
 wherein the body chip includes:   a decryption processing unit capable of performing a decryption process multiple times; and   a timer for measuring the authentication time,   wherein the authentication determination unit outputs a challenge code to the first encryption processing unit as the authentication execution instruction,   wherein the first encryption processing unit performs the encryption process multiple times with respect to the challenge code, and then outputs a first response code to the decryption processing unit,   wherein the decryption processing unit performs the decryption process multiple times with respect to the first response code, and then outputs a second response code to the authentication determination unit,   wherein the authentication determination unit determines whether the challenge code and the second response code match or not,   wherein if the challenge code and the second response code match each other, the authentication determination unit determines whether the authentication time measured by the timer is within a predetermined time,   wherein if the authentication time is within the predetermined time, the authentication determination unit determines that the sub chip is valid.